The present invention relates to a small information processing apparatus having a relatively small display screen, and in particular to a small information processing apparatus of a type that can switch the mode for displaying data on the display screen to a portrait mode or to a landscape mode. More specifically, the present invention retains to a small information processing apparatus that provides appropriate scroll functions for both display modes, i.e., the portrait mode and the landscape mode.
In accordance with recent technical developments, various types of personal computers (PCS), such as desktop, tower and notebook types, have been developed and are being sold on the market. The notebook computers, designed while taking portability into consideration, are compact and light battery-operated computers. Lately, portable information terminals (also called "PDA (Personal Digital Assistants)"), which are smaller than notebook PCS, have appeared.
Portable information terminals, which are compact and thin enough to be held in user's palm, are designed to be employed not only on desk in a home, in a school or in an office, but also in mobile environments, such as on a train, bus or airplane, and outdoors, in such places as park. The sufficient storage of information to support user's daily works is demanded for this type of portable information terminal. Specific applications for a portable information terminal include (1) the support of unique ideas, by providing an idea processor; (2) the support of individual activities, by providing an electronic secretary function; and (3) the provision of appropriate information, by searing through a large quantity of data stored in memory. A definitive description of a portable information terminal has not yet been provided; even the form of user interface varies, and can be, for example, key input interfaces or tablet input interfaces. Also, the sizes of portable information terminals are not standardized; units may range in size from those that have approximate A5 size foot print to those that are the size of a business card.
For example, a PC card "IBM ChipCard VW-200" (hereinafter referred to simply as "VW-200"), sold by IBM Japan, Ltd., is a self-contained, functioning unit that employs an incorporated MPU. (The well known international standards for PC cards are determined primarily by PCMCIA (Personal Computer Memory card International Association) and JEIDA (Japan Electronic Industry Development Association)). That is, the VW-200 is driven by an incorporated coin battery and provides a calculation function and a data viewer function, and also acts as a portable information terminal.
VW-200 is a PC card of folding type that is constituted by a first housing portion having a Type form factor defined by PCMCIA/JEIDA, and a second housing portion rotatably connected to one end of the first housing portion. A PCMCIA connector is located at the other end of the first housing portion to provide a PCMCIA interface, and a liquid crystal display of 200.times.320 dots is recessed in the surface of the second housing portion. A lot of 20 characters.times.0.12 lines in the full-sized Japanese character mode can be displayed at one time on the liquid crystal display. Normally, the portrait mode is employed to display data on the display screen.
When VW-200 is inserted into an external computer system, for example, the computer system can download stored data via a PCMCIA interface to a memory incorporated in the VW-200. When the VW-200 is removed from the computer system, the VW-200 can display, without the involvement of the computer system, the downloaded data on the screen of the second housing portion. The data that are downloaded from the computer system may be PIM data, such as schedules and addresses, and text data from a Web page acquired in advance by the computer system.
The data that are expected to be viewed in the mobile environment by a small portable information terminal, such as VW-200, include Web pages and PIM data. These data are edited and accumulated in advance by an external computer system, and the resultant data are downloaded to a memory device in the VW-200. Web pages that are especially desired for reference purposes in mobile environments are the regular newspaper articles, and pages carrying data that require for prompt action, such as Stock Market, Weather, and Traffic Information. PIM data that are especially desirable for reference in a mobile environment are those for a Phone Book, an Address Book, the calendar and schedules.
There are a variety of display data types and their characteristics also vary. For example, data for the regular newspaper article are structured only as relatively long character strings, and whether or not an article is legible does not much depend on the direction in which it is displayed on the screen. However, stock market data are arranged as tables of company names and stock prices, and weather data are arranged as tables of local area names and corresponding climatic conditions. In other words, these data are text data into which line returns are inserted at intervals following relatively short character strings, and accordingly, for them the longitudinal side of a display is disposed perpendicularly. On the contrary, for the address data, the number of characters in a line must be increased so that relatively long local area names can be displayed. And for schedule data, especially if they are shown with hourly entries for an entire day, the number of characters in a line must also be increased. In other words, unlike for stock market data and weather data, for the display of data for addresses and schedules, the longitudinal side of a display is horizontally disposed.
If an information processing apparatus has a large display screen, it absorbs differences between the characteristics of various types of data displayed on its screen. However, a portable information terminal generally has only a relatively small display, and thus, whether data are readily apprehended by a user is greatly influenced by the manner in which the data are displayed, in portrait mode or in landscape mode. For example, the display screen of the VW-200 is only 20 characters.times.12 lines in full-sized Japanese character mode. If text data (e.g., schedule data), the longitudinal direction of which is horizontal, are displayed in portrait mode, frequently the data for one line will exceed the screen width, and accordingly, a user will be required to scroll the screen from side to side. On the other hand, if text data (e.g., market stock data), the longitudinal direction of which is vertical, are displayed in landscape mode, the number of data sets that can be displayed on one screen is reduced, and an area where no data is displayed is large. This is very inefficient.
Text is not easy to read if the ends of liens are cut off, and frequent scrolling a screen horizontally is an annoying task for a user. It is better for a user that text data, the longitudinal side of which is vertical, is displayed in portrait, and that the text data, the longitudinal side of which is horizontal, is rotated at 90.degree. (or 270.degree.) and displayed in landscape. Therefore, several information processing apparatuses that permit the data display direction to be changed from portrait to landscape, or vice versa, have been proposed. For example, in Japanese Unexamined Patent Publication No. Hei 8-129557 is disclosed a portable electronic reading apparatus that changes the display direction in accordance with whether the apparatus is settled in portrait or landscape posture. According to this invention, since an article can be efficiently displayed by a reader merely changing the direction in which the body of the apparatus is oriented, in the same manner as one would change the direction in which a magazine is oriented, the data is very easy to see and usability is superior.
When the screen display direction is changed, however, new problems, i.e., problems concerning the scrolling and the cursor operations, arise. For example, in Japanese Unexamined Patent Publication No. Hei 4-88545 is disclosed a palmtop information processing apparatus of a portrait display type. A rotary switch for cursor movement is provided on the left side of the main body of the information processing apparatus. The left circumferential edge of the rotary switch is exposed outside the main body for manual manipulation. The clockwise rotation or the counterclockwise rotation of the rotary switch, i.e., the vertical movement of the exposed portion when manually manipulated, shifts a cursor vertically, so that operation of the cursor is intuitively performed by a user. However, for an information processing apparatus having only a single rotary switch, when the display screen direction is changed, for example, from portrait to landscape, the degree of intuitiveness involved in the curser/scrolling operation is reduced. This is because when the apparatus is disposed horizontally, the exposed portion of the rotary switch must be rotated horizontally by a user, and this direction does not correspond to the screen scrolling direction, i.e., the vertical direction. It should be noted that the subject of Japanese Unexamined Patent Publication No. Hei 4-88545 does not include the conversion of the screen display direction.
The apparatus disclosed in Japanese Unexamined Patent Publication No. Hei 8-129557 provides four scroll keys that enable the scrolling operation to be performed vertically and horizontally, in four directions. The directions in which the respective scrolling key indicate are automatically converted in accordance with the display mode, so that the intuitiveness of the scrolling operation can be maintained, even when the screen display direction is changed from portrait to landscape or vice versa. However, according to the invention in this publication, maintenance of the intuitiveness involved in the scrolling operation is possible only by the provision of a plurality of scrolling keys, i.e., by increasing the number of components. In other words, the invention described in the above publication can not provide intuitive performance of the scrolling operation for an apparatus that has only one scroll operation means, such as a single rotary switch.
Conventionally, a keyboard or a pen is employed as an input device for a portable information terminal. It is difficult, however, to provide multiple keys because of the limitations imposed by the size of the apparatus. In addition, carrying a dedicated pen for input is inconvenient. Furthermore, a user must use both hands for an input operation when employing a keyboard or a pen, and this can result in suspension of ongoing job.
In other words, a function is required whereby intuitive data scrolling using only one hand is possible in either the portrait mode or the landscape mode.